电动负载模拟器的重复控制器的设计

通过分析电动负载模拟器的基本结构和工作原理,建立数学模型并且分析了多余力矩产生的机理,提出一种重复控制和PID控制相结合的复合控制策略,利用重复控制改善系统的稳态特性,利用PID控制改善系统的动态特性.仿真结果表明,所采用的方控制方法能够有效地抑制多余力矩,提高了系统的稳态精度和动态性能.     

输入饱和及带宽限制下高超飞行器的闭环稳定边界研究

针对于吸气式高超声速飞行器开环不稳定的动力学特性,研究了控制信号存在饱和约束及带宽限制条件下的闭环稳定边界.首先,简要介绍了吸气式高超声速飞行器的建模方法与动力学特性的主要问题.考虑到飞行器控制信号的幅值限制及带宽约束,综合高超声速飞行器的开环不稳定特性,定量地分析了系统的闭环稳定边界:与系统不稳定极点的位置,其对应的左特征向量及控制信号的幅值约束有关;执行器的带宽限制在此基础上进一步缩小了反馈控制系统的稳定边界.根据高超声速飞行器短周期不稳定特性,解析地给出了闭环稳定边界的计算公式.采用蒙特卡洛分析方法对闭环系统的稳定边界及滑模变结构控制器作用下的稳定区域进行验证.仿真结果与理论分析具有一致性,验证了系统开环特性对于闭环稳定性的限制及控制信号带宽约束对稳定性的影响.     

基于单片机的电梯控制仿真系统

提出了一种以单片机系统负责模拟用梯指令信号的采集,以PC上位机软件对指令信号进行处理结果反馈控制的电梯控制仿真系统框架.在电梯控制仿真系统软件设计的基础上,采用模块化设计的方法,研究了基于单片机的电梯控制仿真系统的控制策略和硬件设计.该系统使用和扩展方便,为各种新型电梯控制技术的进一步研究提供平台.     

基于STM32的泵控马达恒速输出系统的设计

为实现泵控马达系统输出恒转速,建立了系统的液压工作原理,通过对泵控马达调速系统的整体控制设计,确定了以STM32单片机为核心的信号控制器.系统的控制器包括硬件部分和软件部分,从而使该信号控制器将PID控制与PWM信号输出相结合,通过调节控制电压调整变量泵的排量,以抑制外接转速波动影响,从而实现1500r/min恒速输出.通过搭建系统实验平台,对系统的调速特性进行实验验证,得到了系统控制电流与转速的关系,以及控制信号突变对系统响应的影响.最后验证了系统在转速扰动下的调速特性,结果表明本系统具有较好的调速能力,达到国家Ⅲ类发电要求.     

硅微Z轴谐振陀螺仪闭环伺服控制系统设计

根据自行设计的硅微Z轴谐振陀螺仪的工作原理,提出了闭环伺服控制系统模型,在对开环检测模型分析的基础上设计了闭环伺服控制系统,并用Matlab软件对闭环伺服系统的频域和时域特性进行了仿真分析,选取了合适的校正环节及优化参数,使系统有较高的稳定裕度和较好的动态特性.通过实验调试实现了初始检测电容差引起的信号以及正交信号的反馈抑制控制,达到了较高的控制精度.     

电动助力转向系统控制策略研究

本文介绍了电动助力转向系统的结构和工作原理,建立了该系统的动力学模型,进一步提出了系统的助力控制、回正控制以及动态阻尼控制策略.策略中采用了PI控制和PID控制方法,并讨论了控制器增益的变化对转向特性的影响.通过仿真分析比较,证明采用此控制策略的EPS能减轻汽车的转向操纵力,改善汽车的回正特性.     

基于振动特性分析的采煤机煤岩识别控制系统

针对采煤机截割过程中的煤岩识别及滚筒自动调高控制问题,提出并设计了一种基于振动特性分析的采煤机煤岩识别控制系统。该系统采用传感器检测采煤机滚筒在截割煤岩过程中3个方向的振动信号,采用PLC进行振动信号的分析和处理,得到采煤机滚筒在截割煤岩过程中的振动特性规律,由此建立采煤机滚筒调高控制规则表,并通过反馈信号偏差在线查表和控制信号输出的闭环控制方法实现采煤机滚筒的自动调高控制。相似模拟截割试验结果表明,该系统能够较好地实现煤岩界面识别和滚筒自动调高控制,具有良好的动态性能。     

原子力显微镜微悬臂梁的混沌运动控制

通过数值模拟方法分析了原子力显微镜（atomic force microscopy,AFM）微悬臂梁的混沌运动与分岔特性,研究了“时间延迟反馈控制”、“周期信号控制”分岔特性和混沌运动控制参数的取值范围,以及同一周期轨道不同控制参数的值域．研究结果对复杂系统非线性动力学行为分析和混沌运动控制提供了有意义的理论参考,同时对控制原子力显微镜主要构件的运动和改善其测量精度,具有工程实用价值．     

大气数据仪表校验系统的设计与实现

针对飞机大气数据计算机和测试仪表的校验问题,在分析了大气数据仪表的特点的基础上,基于嵌入式计算机控制技术和精密气压控制技术,提出了一种智能大气数据校验系统的设计方案;从控制方面,系统采用双传感器、普通硅压阻压力传感器和数字石英压力传感器,模拟传感器具有高速响应特性,将其作为过程控制传感器,保证装置的动态响应性能;数字石英压力传感器的精度达0.01%F.S,作为基准压力传感器,保证系统准确度;采用双闭环控制方案,模拟闭环采用电子电路设计实现,采用模拟硅压阻压力传感器和模拟PID控制电路构成模拟控制闭环;采用数字式压力传感器和计算机构成数字PID控制闭环,数字闭环通过计算机、数字传感器、软件、串口和计算机串口实现;实验证明,该装置升降速度的输出准确度优于0.02%F.S,控制稳定性0.002%F.S。     

一种基于时域响应的预测控制算法的研究

针对工业控制过程中系统具有大滞后这一特性,给出了一种基于时域响应特性的预测控制算法.该算法利用当前及之前的采样信息和已输出的控制信息预测系统的未来输出,获得使系统无偏差的控制信号,使得系统的性能指标最优.理论分析和Matlab仿真试验验证了该算法的可行性.该算法计算简单、鲁棒性强、抑制干扰能力及跟踪性能良好,对大时滞一阶系统具有较理想的控制效果.     

Mode‐dependent seamless transfer control strategy of a microgrid via a small‐signal stability approach

A microgrid is an effective solution to enhance the integration of distributed renewable energy resources, which can operate both in grid connected mode and islanded mode. In order to reduce the jumps of the system variables within acceptable limits to ensure the system has good transient performance and power quality in multiple operating modes, seamless transfer is the key problem to be considered. In this paper, due to the different multiple equilibrium points for the two operating modes, the dynamics of every operating mode re modeled as a subsystem with all the variables that are needed to be synchronized. Linearization is carried out respectively for the two operation modes on the different equilibriums in a state‐space form based on the small‐signal stability method. To reduce the conservatism of the unified controller, the concept of the relative Lyapunov function is introduced to derive a multiple segmental Lyapunov method and a robust feedback mode‐dependent switching controller is designed to achieve smooth transfer by making the deviation energy of the two modes both converge to the zero point. To rapidly detect the switching signal, a sparse communication network is introduced by the use of low bandwidth communication links to broadcast the switching signal to each distributed controller. Finally, two microgrid test systems were built in SIMULINK to show the feasibility and effectiveness of the proposed seamless transfer control strategies.     

Fully Evolvable Optimal Neurofuzzy Controller Using Adaptive Critic Designs

A near-optimal neurofuzzy external controller is designed in this paper for a static compensator (STATCOM) in a multimachine power system. The controller provides an auxiliary reference signal for the STATCOM in such a way that it improves the damping of the rotor speed deviations of its neighboring generators. A zero-order Takagi–Sugeno fuzzy rule base constitutes the core of the controller. A heuristic dynamic programming (HDP) based approach is used to further train the controller and enable it to provide nonlinear near-optimal control at different operating conditions of the power system. Based on the connectionist systems theory, the parameters of the neurofuzzy controller, including the membership functions, undergo training. Simulation results are provided that compare the performance of the neurofuzzy controller with and without updating the fuzzy set parameters. Simulation results indicate that updating the membership functions can noticeably improve the performance of the controller and reduce the size of the STATCOM, which leads to lower capital investment.      

机器人控制器核心设备的实时性研究

机器人控制器核心系统的实时性提高与改进是一个关键问题,结合机器人控制器的特点对操作系统平台的实时性进行分析,着重比较了Linux操作系统和改进的RTLinux实时操作系统在实时性上的区别,对机器人控制器任务采用多线程机制进行实时域和非实时域的重新划分,并提出一套实时性改造方案,完成机器人控制器的任务,最后给出了一个在RTLinux操作系统下实现硬件设备实时驱动程序的一个例子。     

Development of a rapid-response flow-control system using MEMS microvalve arrays

A method for providing high-resolution gas flow control using microelectromechanical systems (MEMS) has been developed and tested. The micromachined component consists of an array of 61 synchronized microvalves operating in parallel. A number of tests were conducted on microvalves of various designs to characterize their operation. The best performing of these was used with a prototype flow controller. Additionally, a mathematical model of the flow system and controller was derived to predict the response of the system to various changes in operating conditions. This work describes the design, modeling, and testing of a compact, stand-alone mass flow controller (MFC) to demonstrate high resolution, fast response flow control using MEMS microvalves. The device consists of a microvalve array packaged with a micro flow sensor and a microprocessor-based control system. The high bandwidth of microvalves allows an atypical flow control architecture. The controller regulates a pulsewidth-modulated (PWM) signal sent to the valve array and is capable of both open- and closed-loop control. A mathematical model was also developed to predict the dynamic performance of the system under various operating conditions. Additional advantages of the MEMS flow-control system include low-power consumption, low fabrication costs, and scalable precision.     

Small-signal modeling and controller design of energy sharing controlled distributed battery system

This paper presents small-signal modeling, analysis and closed-loop controller design guidelines for a distributed battery energy storage system with energy sharing controller which has recently been presented in the literature in order to achieve cell balancing with high cell balancing speed and energy efficiency. The derived small signal models provide deeper insight into the dynamics of the energy sharing controlled battery system under different operating modes, including discharge mode, constant current charging mode and constant voltage charging mode. Based on the derived small signal models, closed-loop controller design guidelines are provided based on rule-of-thumb frequency-domain design criteria. The small signal models and designed controllers are validated by MATLAB®/SIMULINK simulation and experimental prototype results.     

高温超导磁梯度仪测控系统的设计与实现

针对高温超导磁梯度仪手动调节控制器操作繁琐,工作效率低的问题,设计并实现了一种高温超导磁梯度仪的自动测量控制系统;通过实时采集和分析超导量子干涉器输出的调制三角波信号,自动调整其工作点参数,实现高温超导磁梯度仪的自动调试功能。通过微处理器控制前置放大器内的锁相环路的闭合,实现高温超导磁梯度仪信号输出;设置大容量Flash存储器实现仪器工作点参数和测量数据的存储;采用光电隔离技术,降低了测量控制系统对仪器前端工作电路的噪声干扰;实验结果表明,设计的测量控制系统在野外可稳定可靠工作,效率高,方便了高温超导磁梯度仪在地球物理磁法勘探中的应用。     

一类双悬臂含间隙振动系统的混沌控制策略研究

由于一类双悬臂含间隙振动系统具有典型非光滑特性和有明显的非线性,这直接导致了系统发生分叉与混沌现象的可能性.为此针对该系统的混沌现象,利用基于能量的开环控制策略,构造有界控制器对混沌行为进行控制,混沌运动可被引导到稳定的目标周期轨道,并对控制的收敛速度进行分析,数值模拟结果表明了该控制策略的有效性与可行性,可为碰振系统的优化设计,振动控制和安全运行提供了理论参考.     

Reference model selection and adaptive control for induction motordrives

An adaptive model-following speed controller for induction motor drives is proposed and implemented. This adaptive controller is easy to implement since, for the controlled plant, only the output signal is fed back. In order to choose a reference model with the desired drive dynamic behavior, a two-degree-of-freedom (2-DOF) controller is designed, using a systematic procedure based on the prescribed drive specifications. The reference model of the adaptive system is chosen as the transfer function of the controlled drive system by the 2-DOF controller in the nominal case. An adaptation signal is augmented to let the prescribed specifications be maintained under a wide range of operating conditions     

电涡流传感器在混合悬浮控制器中的应用

位移信号传感器作为磁悬浮系统的一个信号采样装置,用来检测悬浮磁铁的位移信号,并将该信号传送给控制器,作为控制器进行控制和调节的参考信号,位移传感器工作性能的好坏将决定着整个控制系统能否正常工作。介绍了电涡流传感器的工作原理、结构及其在混合悬浮控制器中的应用。实验结果表明：电涡流传感器应用于混合悬浮控制器中,灵敏度高,结构简单,抗干扰能力强,为进一步提高混合悬浮控制系统的精度给出了新的途径。     

Robust self-tuning PID controller for nonlinear systems

In this paper, we propose a robust self-tuning PID controller suitable for nonlinear systems. The control system employs a preload relay (P_Relay) in series with a PID controller. The P_Relay ensures a high gain to yield a robust performance. However, it also incurs a chattering phenomenon. In this paper, instead of viewing the chattering as an undesirable yet inevitable feature, we use it as a naturally occurring signal for tuning and re-tuning the PID controller as the operating regime digresses. No other explicit input signal is required. Once the PID controller is tuned for a particular operating point, the relay may be disabled and chattering ceases correspondingly. However, it is invoked when there is a change in setpoint to another operating regime. In this way, the approach is also applicable to time-varying systems as the PID tuning can be continuous, based on the latest set of chattering characteristics. Analysis is provided on the stability properties of the control scheme. Simulation results for the level control of fluid in a spherical tank using the scheme are also presented.